Originally published in The News newspaper May 13, 2011
Q: I am new to Mexico City and am having trouble baking in this high altitude. What changes to I need to make, especially with breads and cakes? Nothing seems to come out right.
Janice, Mexico City
A: High altitude presents several challenges when preparing some foods. Baked goods may rise quickly only to completely collapse and foods that are cooked in water or moist heat take much longer to prepare. The higher the elevation, the lower the air pressure, so there is less pressure on leavened products and the surface of boiling liquids. As atmospheric pressure decreases, water boils at lower temperature. At sea level it boils at 212°F, while in Mexico City’s altitude of 7,400 feet, water boils at around 199°F. Adjustments to recipes need to be made to compensate for the reduced air pressure and water boiling point.
The following are some general guidelines to follow when cooking or baking in Mexico City. You will need to experiment a bit to find what adjustments work best for your recipes. In general, you should try minimal modifications the first time you prepare a recipe and adjust as needed subsequently.
Baking
* With less air pressure weighing them down, leavening agents such as baking powder tend to work too quickly at higher altitudes. By the end of baking time most of the gasses have escaped, resulting in deflated baked goods. You will need to reduce the amount of baking powder by 1/8 to 1/4 per teaspoon.
* For cakes leavened by egg whites, beat only to a soft peak consistency. This will keep the cake from expanding too much as it bakes and then collapsing, leaving the cake flat.
* Raise the oven temperature by about 25° and slightly shorten baking time. Invest in an oven thermometer so you know the exact temperature of your oven.
* Always pre-heat your oven for at least 15 minutes to bring it up to the correct temperature.
* Flour tends to be drier at high elevations, so increase the amount of liquid in the recipe by 3 to 4 tablespoons.
* Acidity helps batter set quickly in the oven's heat, so replacing regular milk with buttermilk, sour cream, or yogurt can be helpful.
* Decrease the amount of sugar by 1 to 3 tablespoons for each cup of sugar called for in the recipe.
* Cookies can sometimes spread too much or get tough. Try using less sugar, leavening, or fat. They may also need a little more liquid and flour, or try slightly increasing the oven heat (15°F to 25°F).
* Bring eggs to room temperature prior to use and don't over beat them.
* As a general rule, add an extra egg to cake, cookie and muffin mixes. The protein in the eggs strengthens the cell structure and makes up for dryness of the flour.
* These adjustments can be used in both boxed cake mixes or cakes made from scratch.
* Reduce the amount of yeast in bread dough, or shorten the rising time so it doesn’t over-proof (rise too much).
* To achieve good rise and a crisp crust at high altitude, begin baking bread with a pan of boiling water on the bottom of the oven, then remove the water for the final 15 minutes of baking.
Cooking & Frying
* Deep fry foods at a lower temperature for a longer amount of time. If you don’t lower the temperature, the outside will be crispy but the inside may still be raw.
* At 7,400 FT, beans take twice as long to cook than at sea level. I would recommend investing in a pressure cooker if you cook beans often.
* For stews and braises, expect to add about 2 hours to the cooking time.
* Pasta requires a strong roiling boil and longer cooking time.
* Above 5,000 feet, temperatures obtained with a double boiler are not high enough for maximum gelatinization of starch. Therefore, use direct heat rather than a double boiler for making puddings and cream pie fillings. Watch carefully so it doesn’t scorch.
